View Compilation Error

0_0_27050298_24756.cpp:11:9: error: 'maxn' was not declared in this scope
 char s1[maxn], s2[maxn];
         ^
0_0_27050298_24756.cpp:11:19: error: 'maxn' was not declared in this scope
 char s1[maxn], s2[maxn];
                   ^